Suzhou dialect and Wujiang dialect, as two examples of Chinese Wu dialects, have complex tone systems consisting of 7 and 12 lexical tones respectively. In order to overcome the limitations of the traditional 5-level tone code system, the command-response model for the process of F0 contour generation is employed to analyze quantitatively the lexical tones in continuous speech of these two dialects. The analysis shows that there can be as many as three tone commands within a syllable. Not only the polarities but also the timing and amplitudes of tone commands can be varied to distinguish different tones. Especially, the tones sharing the same command polarities are compared in each dialect. By providing both phonological interpretations to each lexical tone and quantitative descriptions to continuous F0 contours, the command-response model shows the validity of being applied to tone languages with very complex tone systems.